Ionospheric Propagation - Electronic Engineering (MCQ) questions & answers

1)   Which ionization layer exists during day time & usually vanishes at night due to highest recombination rate?

a. D-region
b. Normal E-region
c. Sporadic E-region
d. Appleton region
Answer  Explanation 

ANSWER: D-region

Explanation:
No explanation is available for this question!


2)   How is the effect of selective fading reduced?

A. By high carrier reception
B. By low carrier reception
C. By single side band system
D. By double side band system


a. A & C
b. B & D
c. A & D
d. B & C
Answer  Explanation 

ANSWER: A & C

Explanation:
No explanation is available for this question!


3)   According to Secant law, which frequency is greater than critical frequency by a factor of secθi?

a. MUF
b. LUF
c. OWF
d. UHF
Answer  Explanation 

ANSWER: MUF

Explanation:
No explanation is available for this question!


4)   If the maximum electron density for F-layer in ionosphere is 4 x 106 electrons/cm3, then what will be the critical frequency of EM wave for F-layer?

a. 4 MHz
b. 9 MHz
c. 18 MHz
d. 25 MHz
Answer  Explanation 

ANSWER: 18 MHz

Explanation:
No explanation is available for this question!


5)   Which among the following plays a primary role in generation of conduction current in an ionosphere due to presence of electric field?

a. Ions
b. Motion of electrons
c. Neutral molecules
d. None of the above
Answer  Explanation 

ANSWER: Motion of electrons

Explanation:
No explanation is available for this question!


6)   Which mechanism/s is/are likely to occur in mid-frequency operation corresponding to ionospheric region?

a. Only Reflection
b. Only Refraction
c. Partial reflection & refraction
d. None of the above
Answer  Explanation 

ANSWER: Partial reflection & refraction

Explanation:
No explanation is available for this question!


7)   According to Snell's law in optics, if a ray travels from dense media to rarer media, what would be its direction w.r.t the normal?

a. Towards
b. Away
c. Across
d. Beside
Answer  Explanation 

ANSWER: Away

Explanation:
No explanation is available for this question!


8)   F2 layer of appleton region acts as a significant reflecting medium for _____ frequency radio waves

a. Low
b. Moderate
c. High
d. All of the above
Answer  Explanation 

ANSWER: High

Explanation:
No explanation is available for this question!


9)   What is the possible range of height for the occurrence of sporadic E-region with respect to normal E-region?

a. 20 km – 50 km
b. 45 km – 85 km
c. 90 km – 130 km
d. 140 km – 200 km
Answer  Explanation 

ANSWER: 90 km – 130 km

Explanation:
No explanation is available for this question!